1. Field of the Invention
This invention relates to the stuffing of cellulosic food casings with meat emulsions and more particularly to the treatment of the casing to insure the circumferential uniformity of the stuffed and linked casing.
2. The Prior Art
In the preparation of sausages of various types, ranging from small sausages such as frankfurters and viennas up to large sausages such as bolognas, the sausage meat is normally extruded into and encased in a tubular casing formed of regenerated cellulose. Clear, thin-walled (e.g., 1.0 to 1.5 mils) cellulosic casings are used primarily in the preparation of small diameter (22 to 23 mm) sausages such as frankfurters and viennas. Intermediate diameter (e.g., 56 to 58 mm) sausages referred to in the art as "chubs" and large diameter (e.g. 121 to 125 mm) sausages of the bologna type are encased in heavy walled (2.5 to 3.5 mils) cellulosic casings of both the clear and fibrous-reinforced type. In the manufacture of small sausages, the casing is generally stripped from the sausage after it has been smoked and cooked by the meat packer. In the manufacture of intermediate and large sausages, the sausage generally remains encased in the cellulosic casing after the sausage is cooked and smoked by the meat packer.
Regenerated cellulose sausage casings are typically made by the viscose process wherein a cellulosic furnish is treated with caustic soda to form an alkali crumb, the crumb shredded, xanthated and dissolved in caustic soda to form viscose.
The viscose is extruded through an annular die into a coagulating bath to produce a hollow, thin-walled tube of coagulated and partially regenerated cellulose. The tube is subsequently treated in an acid bath to thoroughly regenerate the cellulose and washed to remove by-products. The regenerated cellulose tube is treated with an aqueous solution of glycerine, and dried while inflated under a substantial air pressure for size control. After drying, the casing is wound on reels and subsequently shirred on high speed shirring machines, such as those described in U.S. Pat. Nos. 2,010,626, 2,583,654, 2,722,714, 2,722,715, 2,723,201, etc.
A type of casing known in the art as fibrous casing is manufactured by forming a long fiber hemp paper into a continuous tube, impregnating the tube with viscose, and treating the impregnated tube with a coagulating and regenerating bath to produce a paper reinforced tube of regenerated cellulose. Miscellaneous casing is manufactured in a similar manner to fibrous casing except no paper is used.
In the preparation of small and intermediate size sausages, a sausage paste or emulsion is extruded from a stuffing horn into a shirred sausage casing. In the manufacture of "chubs" which generally weigh less than a pound, the casing is supplied to the meat packer in the form of transparent, printed cellulosic casing having a length in the order of 55 to 66 feet which is compacted to a shirred length of 12 inches. Usually about 100 chubs can be manufactured from a single shirred strand.
To fill the shirred strand with the sausage paste, the strand which is pinched off at one end, is soaked in water to soften the strand and the other end of the moistened strand is mounted over the discharge end of a stuffing horn. The sausage paste is extruded into the casing at a high speed with the result that the entire length of the casing deshirrs and is filled with sausage paste in a few seconds. As the casing is filled with sausage emulsion, it passes into a linking device which twists the casing at predetermined intervals along the filled casing to form a plurality of individual sausage links. The linked strand is fed to a stainless steel stuffing table where it is gathered up after the completion of the stuffing and linking cycles. Thereafter, the linked strand is cooked and/or smoked. After cooking and/or smoking of the encased lengths of sausage, the individual links are separated and wrapped in plastic film packages for shipping.
In preparing intermediate diameter sausages such as chubs, an important consideration is the maintenance of uniform size control, primarily circumferential size, over the stuffed sausage being produced. It is very important that the diameter of the chub be carefully controlled, for if the diameter of the chub exceeds certain limits, the chub cannot be machine packaged as conventional packaging machines are constructed to accomodate only chubs having a limited diameter range. If the chub is oversized and will not fit in the automatic packaging machine, the sausage must be rejected for shipment. Further, if the chub is too dimensionally oversized or misshapen, the chub has an unusual, non-uniform appearance which will be rejected by the consumer.
In the manufacture of chubs, there has been encountered situations in which about 10% of the chubs, i.e., 10 out of 100 of a filled and linked strand of miscellaneous casing have had to be rejected for shipment because of their oversize dimensions.